Faculty of Science, Department of
Biotechnology & Genetic Engineering
Lecturer: Dr. Raida W. Khalil
Internal Examiner: A
Student Name:
Student Number:
Course Name: Molecular Biology
Section: 1
Date: 10th May 2015
Course Number: 240386 2nd Semester: 2014/2015
2nd Exam Time: 9:10 am
Number of Pages: 3 Number of Question: 6
Mark:
Duration: 55 minutes
/20
‘ It is better to understand a little than to misunderstand a lot’
Q1. Consider the following origin of replication that is found on a chromosome. The
sequence of region 1 is shown below. (3 pts)
Region 1: 5’…CTGACTGACA…3’ Top
3’…GACTGACTGT…5’ Bottom
1) Within Region 1, which strand will be the template for leading strand synthesis, the top or
the bottom? ---------------------------------
2) If we assume that a lagging strand fragment is made from region 1, what will be its
sequence? ------------------------------------------------------3) You examine DNA replication in an E. coli mutant, which has a partially defective DNA
polymerase. In vitro experiments using the mutant DNA polymerase gives high an low rate
of error as compared to normal polymerase. Which of the following activities is the mutant
polymerase likely to be missing? Circle correct answer?
a-5’-3’ polymerase b- 3’-5’ exonuclease c-5’-3’ 3-exonuclease d-3’-5’ polymerase
QII Indicate True or False for the following statements ?(2.5 pts)
1-RNA-dependent RNA polymerase is used at some point during the retroviral life cycle to
copy the viral genome. True or False
1
All the best , Dr. Raida W. Khalil
2-RNA-dependent DNA polymerase is used at some point during the retroviral life cycle to
copy the viral genome True or False
3- Polymerase used by the retrovirus to copy its genome forms a covalent bond between a 5’
phosphate and a 3’ hydroxyl. True or False
4-Polymerization of the retroviral genome would be 3’- 5’ True or False
5-Deoxyribonucleotides would be incorporated into the packaged retroviral genome
True or False.
QIII: Choose the most correct answer( 7 pts)
1. SINES (short interspersed elements) are:
a. approximately 300 base pairs long b. LTR containing retrotransposons
c. present in over 1 million copies in the human genome d. a and c
e. all of the above
2. Mobile DNA elements likely contributed to the evolution of higher organisms by the:
a. generation of gene families by gene duplication b. creation of new genes by exon shuffling
c. formation of more complex regulatory regions d. a and b
e all of the above
3. All of the following properties about microsatellite DNA are true except:
a. consist of a repeat length of 1-13 base pairs
b. can cause neurological diseases such as myotonic dystrophy
c. can occur within transcription units
d. a and b
e. all of the above
4. Which of the following class of repetitious DNA is most abundant in the human
genome?
a. simple sequence DNA b. non LTR transposons c. LTR transposons d. DNA transposons
5. Chromosome painting is a technique that involves
a. staining chromosomes with Giemsa reagent
b. hybridizing fluorescent probes to chromosomes
c. hybridizing radioactive probes to chromosomes
d. a and b
e. all of the above
6. Which of the following is a typical feature of prokaryotic genes?
a. polycistronic messenger RNAs b. complex transcription units c. introns
d. a and c e. all of the above
7. All of the following statements about complex transcription units are true except:
a. can have multiple poly A sites b. can generate multiple mRNAs
c. can generate multiple polypeptides d. are common in bacteria
QIV.Use the following items to answer the next three questions. .(3 pts)
a) T-Ag Helicase
b) PCNA
c) RPA d) Primase e) FEN I
1.Separates DNA strands by breaking hydrogen bonds (
2. Maintains DNA template in a uniform conformation (
3. Complex with DNA Pol - δ (
f) Rfc
)
)
)
2
All the best , Dr. Raida W. Khalil
4. Through which daughter duplex DNA passes(
)
5. Removes RNA at 5_ ends of Okazaki fragments(
6. Complex with DNA Pol –α (
)
)
Q.V What is the advantage of complex transcription units over simple transcription
units? (2.5pts)
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------QVI. Describe the similarities and differences between prokaryotic and eukaryotic DNA
polymerases and Poly A polymerase?(2pts)
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Bonus Question: Drop your own Question and answer it properly?
END OF PAPER
3
All the best , Dr. Raida W. Khalil
Faculty of Science, Department of
Biotechnology & Genetic Engineering
Lecturer: Dr. Raida W. Khalil
Internal Examiner: B
Student Name:
Student Number:
Course Name: Molecular Biology
Section: 1
Date: 10th May 2015
Course Number: 240386 2nd Semester: 2014/2015
2nd Exam Time: 9:10 am
Number of Pages: 3 Number of Question: 6
Mark:
Duration: 55 minutes
/20
‘ It is better to understand a little than to misunderstand a lot’
Q1. Consider the following origin of replication that is found on a chromosome. The
sequence of region 1 is shown below. (3 pts)
Region 1: 5’…CTGACTGACA…3’ Top
3’…GACTGACTGT…5’ Bottom
1) Within Region 1, which strand will be the template for leading strand synthesis, the top or
the bottom? ---------------------------------
2) If we assume that a lagging strand fragment is made from region 1, what will be its
sequence? ------------------------------------------------------3) You examine DNA replication in an E. coli mutant, which has a partially defective DNA
polymerase. In vitro experiments using the mutant DNA polymerase gives high an low rate
of error as compared to normal polymerase. Which of the following activities is the mutant
polymerase likely to be missing? Circle correct answer?
a-5’-3’ polymerase b- 3’-5’ exonuclease c-5’-3’ exonuclease d-3’-5’ polymerase
QII Indicate True or False for the following statements ?(2.5 pts)
1- Polymerase used by the retrovirus to copy its genome forms a covalent bond between a 5’
phosphate and a 3’ hydroxyl. True or False
4
All the best , Dr. Raida W. Khalil
2-RNA-dependent DNA polymerase is used at some point during the retroviral life cycle to
copy the viral genome True or False
3- RNA-dependent RNA polymerase is used at some point during the retroviral life cycle to
copy the viral genome. True or False
4- Deoxyribonucleotides would be incorporated into the packaged retroviral genome
True or False.
5- Polymerization of the retroviral genome would be 3’- 5’ True or False
QIII: Choose the most correct answer( 7 pts)
1. All of the following statements about complex transcription units are true except:
a. can have multiple poly A sites b. can generate multiple mRNAs
c. can generate multiple polypeptides d. are common in bacteria
2. Mobile DNA elements likely contributed to the evolution of higher organisms by the:
a. generation of gene families by gene duplication b. creation of new genes by exon shuffling
c. formation of more complex regulatory regions d. a and b
e all of the above
3. SINES (short interspersed elements) are:
a. approximately 300 base pairs long b. LTR containing retrotransposons
c. present in over 1 million copies in the human genome d. a and c
e. all of the above
4. Which of the following is a typical feature of prokaryotic genes?
a. polycistronic messenger RNAs b. complex transcription units c. introns
d. a and c e. all of the above
5. Chromosome painting is a technique that involves
a. staining chromosomes with Giemsa reagent
b. hybridizing fluorescent probes to chromosomes
c. hybridizing radioactive probes to chromosomes
d. a and b
e. all of the above
6. Which of the following class of repetitious DNA is most abundant in the human
genome?
a. simple sequence DNA b. non LTR transposons c. LTR transposons d. DNA transposons
7. All of the following properties about microsatellite DNA are true except:
a. consist of a repeat length of 1-13 base pairs
b. can cause neurological diseases such as myotonic dystrophy
c. can occur within transcription units
d. a and b
e. all of the above
QIV. Use the following items to answer the next three questions. .(3 pts)
a) T-Ag Helicase
b) PCNA
1. Complex with DNA Pol - δ (
c) RPA d) Primase e) FEN I
f) Rfc
)
5
All the best , Dr. Raida W. Khalil
2. Separates DNA strands by breaking hydrogen bonds (
3- Removes RNA at 5_ ends of Okazaki fragments(
4. Through which daughter duplex DNA passes(
)
)
5. Maintains DNA template in a uniform conformation (
6. Complex with DNA Pol –α (
)
)
)
Q.V Describe the similarities and differences between prokaryotic and eukaryotic DNA
polymerases and Poly A polymerase? (2pts)
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
QVI. What is the advantage of complex transcription units over simple transcription
units? (2.5pts)
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Bonus Question: Drop your own Question and answer it properly?
END OF PAPER
6
All the best , Dr. Raida W. Khalil